[4] In 1971, the newly constituted and expanded University of San Diego High School graduated its first coeducational class.

Construction began on CCHS at its current location on Del Mar Heights Road in Carmel Valley in 1999.

[6] Students at Uni were also afforded opportunities to participate in a wide variety of extracurricular activities including fine arts, athletics, clubs, service organizations and leadership roles.

The new school was to have larger facilities to accommodate up to 2000 students, and host many extracurricular activities and sports such as football, swim/dive, water polo, basketball, sailing, soccer, field hockey, lacrosse, softball and baseball.

The majority of these activities had been holding practices and events outside of the Linda Vista campus due to the lack of facilities.

Cathedral Catholic continued all of the traditions from USDHS, including the Dons mascot for the athletic teams.

Those who had names there were honored with a memorial display, which was hung in the USDHS Library at CCHS during the 50th Anniversary Celebration.

Notable dedications for major Uni/CCHS contributors have been engraved into the stone benches and lamp posts around CCHS' quad as well.

[13] At approximately 1600[14] students, CCHS is the largest high school in the Diocese of San Diego.

The Dons maintain a longstanding rivalry with the Catholic all-male high school St. Augustine, known as the Saints; the high-profile annual game between the rivals is called the Holy Bowl.

[24] The film Miracle at Manchester is based on a true story about a student with brain cancer at CCHS, and principal photography took place there.